I don't think the haldex is confused so much as I think there maybe a short input lag that provides that 'drift sensation' on ice. This occurs specifically on iced untreated roads.

 

Yes... but the haldex is employed in a front-rear manner. I can't think how it would be responsible for a side to side motion.

 

The sensation is like a very slow and slight front wheel pull then it corrects/catches itself if you back off the throttle slightly. That seems like the haldex compensating to me, to adjust for various wheels losing traction. I drove a true 4X4 prior to the 2008 LR2 for 21 years, and in 4 wheel drive never felt that 'sensation' but then that was a 1997 4Runner SR5, five speed with locking rear diff (had to add that!!), that I owned from new and totaled on black ice while I was not in 4 wheel drive (dumb).
I use the 18" original LR rims with Hankook i-pikes RW11s (directional). I've driven both vehicles with that model tire for years now.

I am also not certain if the haldex just splits front to rear or more likely to each wheel, front and rear?

 

This makes sense. I’m bringing it in to the shop to see if they can diagnose and I’ll mention your theory. I had been using Nokian Hakkapelitta’s studded (which I have on all my other vehicles with no issues) but I swapped them out this year for some 4 season Toyo’s thinking that might solve the issue but it hasn’t even though the Toyo’s are great on snow.

 

The haldex does not split left to right, it just drives the rear diff.

The rear diff OTH will presumably provide some limited slip so that would result one wheel having more power to the road than the other if there are different traction conditions on each side. Maybe road conditions are not consistent in both wheel tracks.

 

I assume the PTU does the same for the front as well. In bold, since we are talking ice, that's very likely and may also be normal for a AWD vehicle. Hey, it could even be a rutted/slightly worn section of a roadway regularly traveled causing the issue. AWD is definitely not 4WD from my experience but LR has done a very good job with the LR2.
EDIT: Maybe it's the sensation of the back not catching up with the front yet (pushing while front is slightly sliding)? Regardless, pretty sure it's not a suspension/alignment/tire issue.

 

I've always thought AWD was better for packed snow and ice, simply because it can automatically adjust to conditions without driver input and usually has a better overall ride quality than 4WD. 4WD is more suited to off-road than on-road, IMO. Even so, the LR2 is a VERY capable vehicle in off-road conditions.

 

Yes, the PTU would do the same for the front so the same thing is going on up front assuming both tires on one side are in the same track and experiencing the same traction. If the haldex kicks in, you might have just doubled the asymmetric power delivery causing a perceived shift to one side.

Especially if haldex activated BECAUSE the front was slipping too much.

 

Also... the terrain control system uses the ABS to actually apply the brakes selectively to individual wheels to control spin.

Remotely possible you've got a brake mechanical problem on one wheel? If it were an ABS malfunction I'm sure all manner of codes would set. If it's a rear, maybe not noticeable braking on dry pavement?

 

All brakes, lines and fluid have been replaced to date, fluid been changed every two years (twice so far). Hand brake was also serviced and replaced on purchase. I generally service the hand brake annually before the onslaught of winter.

It only happens on iced over roads. Not snow. I am fairly certain that it's not tires, alignment, suspension, brakes, etc. as those areas would most definitely manifest in conditions other than iced over roadways. My .02cents? I think it's the way the AWD system works in this vehicle, like it's a short lag (I also have no ABS faults or errors). Maybe it's a wheel angle or speed sensor malfunction? Lots of electronic variables in a 2008 LR2 for that time period.